The Department also, per Reilly and Grim's report, sent a three page memo to governors of all states outlining federal priorities for enforcing marijuana laws. This included "the distribution of marijuana to minors" and "drugged driving and the exacerbation of other adverse public health consequences associated with marijuana use.Regulating recreational use of marijuana is not on that list.

Justice's decision comes at a time when public support for marijuana is at - excuse the pun - an all time high. Gallup's most recent poll showed that 48 percent of Americans think marijuana ought to be legalized, up from 34 percent about a decade ago.